Build (method = -2) #dp: 5423 Step-3' Graph: 192 vertices and 568 arcs (0.04s) Step-4' Graph: 42 vertices and 268 arcs (0.04s) #V4/#V3 = 0.22 #A4/#A3 = 0.47 Ready! (0.04s) Optimize a model with 81 rows, 269 columns and 728 nonzeros Presolve removed 8 rows and 14 columns Presolve time: 0.00s Presolved: 73 rows, 255 columns, 700 nonzeros Variable types: 0 continuous, 255 integer (36 binary) Found heuristic solution: objective 89.0000000 Found heuristic solution: objective 35.0000000 Optimize a model with 73 rows, 255 columns and 700 nonzeros Presolved: 73 rows, 255 columns, 700 nonzeros Root barrier log... Ordering time: 0.00s Barrier statistics: AA' NZ : 2.980e+02 Factor NZ : 6.490e+02 Factor Ops : 8.555e+03 (less than 1 second per iteration) Threads : 1 Objective Residual Iter Primal Dual Primal Dual Compl Time 0 3.81528927e+02 -6.30116274e+02 2.11e+02 7.15e-02 5.67e+00 0s 1 9.35355343e+01 -2.65211815e+02 4.52e+00 4.44e-16 7.43e-01 0s 2 4.41850263e+01 -1.83571031e+01 1.62e-02 2.22e-16 1.17e-01 0s 3 2.53183849e+01 1.90059260e+01 1.96e-04 3.33e-16 1.17e-02 0s 4 2.50022606e+01 2.49927613e+01 1.89e-14 2.33e-16 1.76e-05 0s 5 2.50000000e+01 2.50000000e+01 1.89e-14 3.33e-16 1.81e-11 0s Barrier solved model in 5 iterations and 0.00 seconds Optimal objective 2.50000000e+01 Root relaxation: objective 2.500000e+01, 187 iterations, 0.00 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time * 0 0 0 25.0000000 25.00000 0.0% - 0s Explored 0 nodes (218 simplex iterations) in 0.01 seconds Thread count was 1 (of 8 available processors) Optimal solution found (tolerance 0.00e+00) Best objective 2.500000000000e+01, best bound 2.500000000000e+01, gap 0.0% Preprocessing time: 0.05 seconds Gurobi run time: 0.01 seconds Total run time: 0.06 seconds Objective: 25 Solution: 3 x [4, 26, 35, 37] 2 x [4, 16, 21, 27] 1 x [2, 3, 12, 30] 4 x [1, 3, 25, 33] 1 x [2, 5, 7, 38] 1 x [1, 10, 32, 36] 1 x [12, 23, 23, 39] 1 x [10, 31, 37, 38] 1 x [10, 28, 29, 34] 3 x [11, 19, 24, 34] 1 x [5, 13, 17, 32] 1 x [9, 16, 26, 30] 1 x [9, 18, 19, 27] 2 x [6, 12, 14, 22] 2 x [6, 8, 15, 20]